1. Field of the Invention
The present invention relates to energy storage systems and, more specifically, to a self-charging energy storage system.
2. Description of the Related Art
Common electrical energy storage systems include electrochemical storage systems (such as lithium ion batteries and the like) and capacitors. Batteries are the most widely used electrical energy storage systems as they have a relatively high energy density. Therefore, they are relatively compact.
Most conventional electrical energy storage systems are recharged using external sources of electricity. For example, battery rechargers usually employ a rectifying circuit to convert alternating current to direct current, which is applied to a discharged battery in a predetermined manner. The application of an electrical voltage to the battery reverses the electrochemical process that occurred during the discharge of the battery.
In certain applications, use of an external charging circuit is not practical or desirable. For example, recharging a battery in some biomedical applications can be difficult. Also, in remote sensing and space-based applications, battery recharging can be difficult or even impossible.
Several attempts have been made at recharging batteries using conversion of mechanical energy to electrical energy. For example, some battery rechargers employ a spring-driven generator that, once released, generates a charge that can recharge a battery. However, such attempts generally require an individual to provide the mechanical energy intentionally to the recharger and they tend to produce only a limited amount of energy.
Therefore, there is a need for a system that self-charges an energy storage system.